1. Field of the Invention
This invention relates generally to a threaded fastener and a mating retainer which prevents loosening of the threaded fastener due to rotation, and more specifically to a fishing reel in which a crank handle is rotatably affixed to the fishing reel and attached to the distal end of a crank shaft by a threaded fastener and a retainer.
2. Background
Fishing reels come in various types such as baitcasting fishing reels and spincasting fishing reels. Regardless of type, most fishing reels provide a crank handle which can be used to rotate the line spool to facilitate rewinding of the fishing line. Typically the crank handle is attached with a threaded fastener such as a conventional nut. To prevent loosening of the nut during operation of the fishing reel, various retainers have been used to prevent rotation of the nut relative to the crank shaft and crank handle.
A limitation of conventional retainers has been that a second threaded fastener has been required to attach the retainer to the crank handle. This second fastener has typically been a small screw which is easily lost during reel maintenance and the tightening of which creates an extra manufacturing step.
Previous attempts have been made to alleviate this problem. For example Asano et al., U.S. Pat. No. 5,690,290 discloses two techniques for eliminating the second fastener. First, a retainer is disclosed which utilizes an interference press fit between a recess in the crank handle and the retainer. This eliminates the tightening of a second threaded fastener, thereby providing an advantage from the manufacturer's perspective. However, this technique makes disassembly during maintenance virtually impossible without damaging either the crank handle or the retainer. No means is provided to remove the retainer. The second technique which Asano discloses for eliminating the second fastener utilizes four chamfers which protrude through openings in the crank handle to secure the retainer to the crank handle. Disassembly of this fishing reel will require all four chamfers to be simultaneously placed in their respective release states before the retainer may be removed. This feat would be very difficult without employing a specially made tool.
A further limitation of conventional retainers has been that sharp inside corners in the outside surface have proven difficult to clean and therefore tend to collect contaminants.
Another limitation of conventional retainers has been that discontinuities in the exposed surfaces of the retainers have proven to be a source of line entanglement.
Thus it is an object of the present invention to provide an attachment which secures the crank handle to the crankshaft including a threaded fastener and a retainer to prevent loosening of the threaded fastener without the need for additional elements to secure the retainer.
It is another object of the present invention to provide a retainer which may be readily removed for disassembly of the fishing reel.
It is another object of the invention to provide a retainer which has a smooth outside surface to reduce collection of contaminants and to discourage line entanglement.